1983-1984 BMW Euro Motronic Engine Computer.  This is a rare DME that was used with Euro M30 High compression (10:1) motor with 218HP , No Lambda control and slide valve type Idle control.  

Up for sale is a Working, in excellent condition BMW E24 635csi Motronic ECU. Bosch Part number-- 0 261 200 011 (0261200011) . This ECU should work with some of the following models: E28 533i 535iE24 633csi 635csiE23 733i 735i Please check the part number off your original before buying, as there are several different types of these.  This unit is from an european model, NOT the US model car and therefore is intended for use without a cat converter.  This unit does not have the control systems for driving a cat converter.  If you have an early 80's fuel injected e28 or E24, and it;s a "grey market" or european car - check your ECU, you probably have this unit.  Common to 83 and 84 models.

633, 533, 535, 735, 733, 635

Check my other store items, I probably have what you need if this is not the one. This is one of the most common no start or random stalling problems with these Motronic ECU controlled cars. If yours does not have this problem, keep an extra ECU in the trunk, you might some day be glad you did... This unit from a BOSCH Authorized service center was once $2792.80, and has been NLA for years now. Get a good used one here from me, with a 30 day functionality guarantee for 1/6 that price!